Having said that, it's not like you can blame Bush for bad planning in Louisiana. The people lived in a friggin' bowl surrounded by water! Now you can certainly blame Bush for having diverted thousands of National Guard (Iraq) and hundreds of billions (Iraq) but that's about it.
You could blame Bush for that, except it hasn't affected the hurricane response:
78,000 of the roughly 440,000 National Guard troops nationwide are deployed overseas.
That said, 24 hours before Katrina landed, I kept hearing and reading of officials on the news talking about the number of guardsmen who had been called up and were standing by for immediate deployment; 200 guardsmen here, 500 guardsmen there, maybe 1500 total. WTF?? CAT5 hurricane and only 1500 guardsmen were standing by for deployment? Now there are 10,000+ more on the way. There should have been that many ready to begin with.
What appears to have happened, in part, early reports were that New Orleans was 'spared' from any considerable damage, while areas east of N.O. near Biloxi were practically leveled. Katrina landed further east of N.O. than predicted. All those immediate response assets standing by around MS, LA, AL, TX, and TN, were directed to areas reported hardest hit (east of N.O.). THEN, the levy around N.O. broke and flooded the city. 70% of the city was DRY several hours after Katrina passed, then the water came pouring in. Its hard to redirect that kind of effort once it has already been committed.
It would also seem officials hugely underestimated the number of persons who would stay behind, whether by choice or not. I cannot believe these people didn't take even the most basic short-term preparations, such as filling empty milk jugs, 2 liter bottles, whatever they could find, with clean tap water and caching some canned goods. They had two to three days advanced notice. Tap water doesn't come out of coin-operated fixtures and a mixed case of canned soup, stew, beans, and the like can be purchased for less than $20. Most of these people aren't that damned poor, unless they have drug and alcohol habits to feed (priorities, you know), or are sickly.
I expected some people to have no means of preparing, but it appears that NONE of these people took ANY short term preparations. It doesn't take a college degree and a good income to think "Hmm, maybe I should fill some of these empty malt liquor bottles with tap water...just in case."